Terpene- and rosin-modified phenolketone-formaldehyde resin and method of preparing same



Patented M 13, 1941 I 2,241,422 I i 'rEnrENE- AND ROSIN-MODIEIED PHENOL-mz'rona romvmmanrnn nnsm AND METHOD or rnaraama SAME Israel Rosenblum,New York, N. Y.

Serial N0. 193,448

No Drawing. Application'Ma rch 2,1938,

15 Claims. 21. 260-25) My invention relates to synthetic resins suitablefor the manufacture of coating compositions, and more particularly tothe production of oil-soluble resins composed of a phenol, a ketone, andan aldehyde, a liquid terpenic material and an acidic natural resin,with or without a neutralizing agent, such as glycerol.

The present application is a continuation-inpart of my copendingapplications Ser. 1 No. 538,248, filed May 18, 1931; Ser. No. 580,495,filed December 11, 1931;. Ser. No. 59 ,379, filed February 20, 1932; andSer. No. 628,298, flied August 11, 1932.

Resins composed of a phenol, a ketone and an aldehyde, especiallyformaldehyde, are not soluble in oily glyceridic esters, such as varnishoils, but their presence in varnishes is highly desirable because oftheir high melting point, durability and color stability. on the otherhand, rosin and other acidic natural resins and their glycerol estersare readily soluble in varnish oils, but the films obtained therewithare not entirely satisfactory, among other reasons, because of their lowdegree of hardness and durability.

It is, moreover, desirable to incorporate relatively' large proportionsof formaldehyde in a phenolic resin which is to be employed in a coat- 7ing composition because with such higher proportions of formaldehyde, aharder and more durable resin is generally obtained. Higher proportionsof formaldehyde, however, render the phenolic condensate, includingthose made with a ketone, even less compatible with varnish oils. Thesehigh formaldehyde resins are difficult to incorporate in oils even withthe aid of rosin or ester gum, for the phenolketone-formaldehydecondensate is thermo-setting in character and shows a strong tendency toprecipitate .out when heated with rosin or ester gum. This isparticularly true when it is sought to incorporate relatively largeproportions, say 8 to 20% of the phenolic resin in the ester gum; whenthe formaldehyde content is high, for example 1 mols to each mol ofphenol, it is even more dimcult to combine the phenolic resin with theester gum and the latter will keep in suspension only small proportionsof the phenolic resin.

It is accordingly the general object of the invention to provide animproved process whereby condensates of a phenol, a ketone and analdehyde, preferably formaldehyde, in such proportions and condensedunder such conditions as to yield a thermo-setting resin may be combinedin relatively large amounts with rosin or esterifled rosin or equivalentacidic natural resin and yield a resinous composition which is solublein varnish oils, such composition being of improved character, ascompared with the rosin or rosin ester, in respect of durability,alkali-proofness and melting point by reason of its content ofphenol-ketone-aldehyde condensate, the product bean oil-soluble resinouscomposition which in the form of an oil varnish, such as a solution inlinseed oil, has the property of drying on porous surfaces withoutpenetrating the same, thereby making the varnish useful foroverprinting" purposes. Other objects will be apparent from the moredetailed description of the invention hereinafter.

According to the present invention the condensation product of a phenol,a ketone and an aidehyde, the phenol being'preferably first condensedwith the ketone in known manner, is combined with or incorporated inrosin or, ester gum with the aid of a'liquid terpene, preferably oneboiling higher than turpentine, for example, dipentene, pine oil,terpineol, and the like. I have found that with the aid of the terpenicmaterial proportions of phenol, ketone and aldehyde which wouldordinarily yield a thermo-setting resin which could not be readilycombined with rosin to any considerable extent to form a homogeneouscomposition, can be readily dissolved in or combined with rosin inrelatively high proportion and even when the proportion of aldehyde,such as formaldehyde to phenol is relatively high, and even when thephenol is one which, like ordinary phenol, yields insoluble resins whencombined with approximately equimolecular or greater proportions offormaldehyde. The liquid terpenic material is preferably employed inrelatively large amount, that is, in quantities of the order of theamount of phenol employed, and even more, since it acts as a verydesirable solvent during the initial stages of the reaction. Theinfluence of the liquid terpene is not however limited to its solventaction; the terpene appears to take part in the reaction, for as much asabout 10% of the liquid terpene based upon the weight of the combinedresin remains incorporated in the solid product and cannot be expelledeven upon heatingto temperatures considerably above the normal boilingpoint of the terpene. It appears therefore that the liquid terpene actsto modify the phenolketone-formaldehyde condensate and perhaps also therosin, in such a manner as to render these materials more compatiblewith each other and the resulting resin readily soluble in varnish oils.

It has already been suggested to incorporate aphenol-acetone-formaldehyde resin in rosin, after which the mixture isneutralized with glycerol, butin such process very great caution must beemployed to avoid precipitation of the phenolic resin: moreover, thephenolic resin is produced with relatively low proportions offormaldehyde. In spite of the fact that the knownphenol-acetone-formaldehyde resin is of low reactivity, it must be addedto the rosin very slowly and at low temperatures .(see United StatesPatent to Amann and Fenrobert No. 1,623,901, Example 5). By the use of aliquid terpene in accordance with the present invention, far morereactive phenol-ketone-formaldehyde resins, that is resins of' theheat-hardening type which become infusible at elevated temperatures, canbe easily incorporated in rosin.

In the preferred manner of carrying out the invention, the phenol andketone are first condensed to produce a diphenylol or homologouscompound. This material is then condensed with a proportion offormaldehyde ranging from about 1 to 3 mols to each mol of phenolicmaterial combined with the ketone, in the presence of colophany and of aliquid terpene, such as dipentene. If desired, the phenoI- ketonecompound and the formaldehyde may first be condensed in the presence oftheliquid terpene and 'then heated with the'rosln. In any event, theproduct is dehydrated up to temperatures of 180 0., the phenolicmaterial remaining in solution or colloidal suspension, the productbeing then neutralized, if desired. Whether neutralized or not, theresinous mass is heated at elevated temperatures to expel excess liquidterpene, a considerable proportion, up to about by weight of theproduct, remaining however chemically incorporated therein.

The invention will be further described in greater detail by way of thefollowing examples which are presented for purposes of illustrationonly.

Example 1 Grams Rosin 1000 Diphenylolpropane 140 40% formaldehydesolution 280 (3 mols for each mol of original phenol) Dipentene 200 Zincacetate 6 are heated together for about twelve hours at the boilingtemperature under reflux (about 100 C.) or at about 110 C. in a closedvessel at about ten pounds pressure. The water is then expelled atelevating the temperature, the temperature being gradually increaseduntil *at about 180 C. an amount of glycerol corresponding to about 10%by weight of the rosin is added. The heating is continued at 180 C. andgradually raised to about 250 C. at which temperature the steriflcationis completed. A very hard resin is obtained which has a melting point ofabout 125 C. and contains'about 5 to 10% of dipentene referred to thetotalweight of the resin, the dipentene being at least partly inchemical combination. The resin is highly suitable for the manufactureof quick drying and highly resistant wood oil varnishes, and withlinseed oil yields-a varnish which is characterized, among other things,by

non-penetration when applied to porous surfaces.

The diphenylolpropane is prepared in known manner by condensing twomolecular proportions oi phenol with one of acetone in the presence of astrong mineral acid such as hydrochloric.

' Example 2 Grams Rosin 1000 Diphenylolpropane 200 40% formaldehydesolution 200 (l mols to each mol of original phenol) Dipentene Zincacetate 6 are heated in the manner set forth in Example 1, the initialreaction product being dehydrated by heating up to 180, at whichtemperature there are added Grams Glycerol Dlpenten 100 and thetemperature gradually raised to 250 C.

and the heating continued until the esteriflcation is complete. Theproduct obtained has a high melting point, having a higher proportion ofphenolic resin than the product of Example 1, and like the latterproduces with vegetable oils highly resistant varnishes, the linseed oilvarnish being especially characterized by nonpenetration.

Example 3 Grams Rosin 1000 Diphenylolpropane 175 40% formaldehydesolution 240 (2 mols for each mol of original phenol) Dipentene 300Glycerol I Zinc acetate 5 are condensed as described in Example L thethe condensates of cresols, xylenols,.the higher phenol homologues suchas butyl and amyl phenols, etc., with acetone, methyl acetone, methylethyl ketone, diacetone alcohol, cyclohexanone, acetophenone and otheraliphatic and cyclic ketones.

Although the acidic quality of the rosin causes this material to actsomewhat in the nature of a catalyst, I prefer to employ an additionalsubstance having catalytic action, as will be noted in the aboveexamples. The various compounds of. zinc, such as the oxide, chloride,acetate, abietate, stearate, etc. have proved to be highly satisfactory,but other catalysts may be employed, including acid, basic and neutralinorganic and organic substances, or combinations of difl'erentcatalysts used in succession, as is well known in the art. If thecatalyst is or forms water soluble material, it may be washed out beforethe dehydration of the initial condensation product.

Under the conditions of the reactions above described, the dipentene hasthe effect of rendering the phenol-ketone-formaldehyde reaction prodnot,which otherwise would be thermo-setting and would tend to separate out,compatible with the rosin and the rosin ester in spite of the relativelyhigh proportion of phenolic condensate and the high molecular ratio offormaldehyde. This effect is undoubtedly due to chemical action of thedipentene on the phenolic condensate since the residual portion ofdipentene, as already stated cannot be expelled even at temperaturesabove its normal boiling point. V The dipentene can be replaced in wholeor part by other liquid terpenes, preferably those boiling above theboiling point of turpentine and particularly pine oil, terpineol and theother indlvldual components of pine oil. While in the above examples theproducts are ultimately esterified with glycerol, such neutralization isnot absolutely necessary. Thus. the initial condensate may be dehydratedand either neutralized only in part or not at all and the acidic productcan then, for example, be run into ester gum, the

acidity of the mixture being thus considerably lower than that of theoriginal condensate. The rosin may be replaced by other acidic resins,especially cracked copal resins.

The resins described hereinabove yieldsolutions of high viscosity andhave a limited solubility in petroleum-thinners like mineral spirits.The varnishes yield films of good body and unusually good colorretention. As indicated in the above examples, the process may becarried out .in two main stages or in a single stage. The varioussubstances can be brought into reaction in different orders except thatit is preferable to condense the phenol and ketone prior to mixing withany of the other materials.

The formaldehyde employed in the above examples may be replaced in wholeor in part by other aldehydes but best results are usually obtained withformaldehyde alone.

I claim:

1. The method of producing an oil-soluble, phenolic resin which iscapable of yielding'nonpenetrating varnishes, which comprises reacting aphenol, a ketone, formaldehyde, an acidic natural resin and a terpenicmaterial of the group consisting of dipentene and terpineol until aninitial resinous condensate is ,obtained, the molecular proportion offormaldehyde to phenol being at least 1:1, and then elevating thetemperature to dehydate the mass, the natural resin being employed inabout 3 to 4 times the combined weights of the phenol, ketone andformaldehyde.

2. The method of producing an oil-soluble, phenolic resin which iscapable of yielding nonpenetrating varnishes, which comprises reacting acondensate of acetone and a phenol of thetype which forms oil-insolubleresins with an equimolecular or greater proportion of formaldehyde, withformaldehyde, an acidic natural resin, and dipentene until an initialresinous condensate is obtained, the molecular proportion offormaldehyde to original phenol being at least 1:1, and then elevatingthe temperature to dehydrate the mass, the natural resin being employedin about 3 to 4 times the combined weights of the phenol, ketone andformaldehyde.

3. The method according to claim 2, wherein glycerol is added to theresinous condensate at a temperature of about 180 C. whereafter the massis heated to about 250 C to complete the esterification.

4. The method according to claim 2, wherein glycerol is present from thebeginning of the reaction, and the temperature is ultimately raised ofphenol-ketone-formaldehyde condensate in' the resinous reaction productis about to 6. The method of producing oil-soluble combinations of aphenol, a ketone and formaldehyde which are capable of yieldingnon-penetrating varnishes which comprises reacting a phenol of the typewhich forms oil-insoluble resins with an equimolecular or greaterproportion of formaldehyde, with acetone and at least a sesqui-molecularproportion'of formaldehyde in the presence of a terpene material of thegroup consisting of dipentene and terpineol, heating the condensate inthe presence of rosin to temperatures sufiicient to cause dehydration,and then neutralizing the mass with glycerol.

'7. The method of producing oil-soluble combinations of a phenol, aketone and formaldehyde which are capable of yielding non-penetratingvarnishes which comprises reacting one mol of diphenylolpropane with atleast 3 mols of formaldehyde in the presence of rosin and of a quantityof dipentene of the order of the weight of phenol, dehydrating the massand then reacting the same with a sufiioient amount of glycerol toproduce-an approximately neutral resin.

8. The method according to claim 1, wherein the condensation takes placein the presence of a relatively small proportion of a zinc compound.

9. A synthetic resin capable. of forming a highly viscous solution in a1:1 mixture of mineral spirits and soluble in varnish oils, said resincomprising the reaction product of a phenol, a ketone,

formaldehyde, a natural acidic resin, a terpenic material of the groupconsisting of dipentene and terpineol, and glycerol, the p enol being ofthe type which does not form oil-soluble resins with equimolecularproportions of formaldehyde, and the formaldehyde being present in atleast about sesqui-mole'cular proportion with reference to the phenol,while the esterified natural resin is present in several times thecombined amounts of phenol, ketone and formaldehyde.

10. A resinous phenolic condensate soluble in varnish oils andcomprising the reaction product of about 1 mol of diphenylolpropane, atleast 3 mol of formaldehyde, dipentene in an amount of the order of thediphenylolpropane, and rosin.

11. A resinous phenolic condensate soluble in varnish oils andcomprising the substantially neutralized reaction product of about 1 molof diphenylolpropane, at least 3 mols of formaldehyde, a compound ofzinc, dipentene in an amount of the order of the diphenylolpropane, androsin.

12. An oil-soluble resin capable of forming non-penetrating varnisheswith linseed oil and comprising the neutralized reaction product ofapproximately 1000 parts of rosin, to 200 parts of diphenylolpropane,200 to 280 parts of 40% formaldehyde solution, and 200 to 300 parts ofdipentene.

13. A non-penetrating coating composition comprising a drying varnishoil having incorporated therein a neutralized condensate of about 1 molof diphenylolpropane, at least 3 mols of formaldehyde, a member of thegroup consisting of dipentene and terpineol in an amount of the order ofthe diphenylolpropane, and rosin.

14. The method of producing an oil-soluble,

phenolic resin which is capable of yielding nonpenetrating varnishes,which comprises reacting diphenylolpropane, formaldehyde and a terpeniomaterial of the group consisting of dipentene and terpineol until aninitial condensate is obtained, the molecular proportion of formaldehydeto diphenylolpropane being at least 2:1, and thereafter heating thecondensate with a quantity of rosin equal to several times the combinedweight of diphenylolpropane and formaldehyde, the

heating being continued until excess terpenic 10 material is expelled.

ISRAEL ROSENBLUM.

